EPA chart of Connecticut's top five releasers of toxins in 2020
The EPA’s 2020 chart of Connecticut’s top five releasers of toxins in the air, water, or land, or by off-site disposal or other releases. Credit: Screengrab / US Environmental Protection Agency

Corporate sites across the U.S are releasing toxic pollution into the surrounding land, air, and water on a regular basis – and often unbeknownst to surrounding communities. Clean Harbours of Connecticut, a hazardous waste company, emitted over 390,000 pounds of toxins into the environment in 2020, topping the state’s list that year.

After an accidental release from a chemical plant in West Virginia in 1985, Congress passed the Emergency Planning and Community Right-to-Know Act. The act established the EPA Toxic Release Inventory (TRI), which provides citizens with crucial information on the toxins being emitted locally and the names of companies doing the emitting. The TRI has allowed certain states to put emission-curbing legislation in place to safeguard public health, as was the case when Massachusetts Gov. Charlie Baker in 2019 passed legislation allocating $2.4 billion to climate change resilience.

Stacker analyzed data from the EPA TRI and the U.S. Census Bureau’s five-year American Community Survey to identify the percentage of each state’s population living in census tracts with toxic release sites, as well as the corporations and facilities responsible for emitting the highest amounts of toxins annually. These results, released in October 2021, reflect the last full year of data, 2020, from the 2020 National Analysis Dataset.

Keep reading to discover where the most toxins are being released in your state, what part of your environment they may be polluting, and who is being affected.

Connecticut’s Numbers

– Population living near toxic release sites: 21.7%
— 20.4% of state’s white population
— 18.3% of state’s Hispanic population
— 18.1% of state’s Black population
— 19.9% of state’s Native American population
— 21.6% of state’s Asian population
— 19.1% of state’s Native Hawaiian/Pacific Islander population
– Total number of sites: 257

Clean Harbours of Connecticut, which is located in Bristol, emitted over 390,000 pounds of toxins in 2020. UniMetal Surface Finishing, a precision parts manufacturer in Thomaston, released nearly 128,000 pounds. Two of the chemicals released into the state’s air that year include dichloromethane (comprising 10% of the toxins released) and toluene (8%).

The EPA’s TRI program recognizes 770 chemicals, with any site that manufactures or uses these chemicals at above-average levels qualifying for listing in the TRI. Chemicals described by the TRI as “toxic” are known to cause cancer or other negative health issues, as well as adverse effects on the environment. Facilities report the amounts of chemicals they release annually to the TRI, with the “release” of a chemical meaning that it is “emitted to the air or water, or placed in some type of land disposal.”

The facilities in the TRI are usually quite large and deal in electricity, metals, mining, chemicals, or hazardous waste. However, not all toxic chemicals used by corporations are listed in the TRI, meaning that its inventory of toxin-emitting sites is not exhaustive.

Keep reading to learn which states have the most and least people living near toxic release sites.

States with the most people living near toxic release sites

#1. Wisconsin: 37.3% of population living near toxic release sites
#2. Iowa: 33.5% of population living near toxic release sites
#3. Wyoming: 32.5% of population living near toxic release sites

States with the fewest people living near toxic release sites

#1. Hawaii: 6.5% of population living near toxic release sites
#2. New York: 8.3% of population living near toxic release sites
#3. California: 8.4% of population living near toxic release sites

A deactivated coal-fired electricity plant in Norwalk, Connecticut. From Canva via Stacker
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Stacker is a news organization that produces and distributes data journalism to the world’s news organizations. Founded in 2017, Stacker combines data analysis with rich editorial context, drawing on authoritative sources and subject matter experts to drive storytelling.